A prosecutor says that a native New Yorker accused of conspiring to join al-Qaeda returned to the United States after pledging allegiance to the group and tried to start his own “mini-al-Qaeda cell.”

Federal prosecutor John Cronan made the accusation against Wesam El-Hanafi Wednesday as the defendant made his first appearance in federal court in Manhattan. El-Hanafi pleaded not guilty and was ordered held without bail.

El-Hanafi was arrested April 30 in Virginia after he was brought to the United States from Dubai, where he had been working. He is charged along with an accountant with conspiring to modernize al-Qaeda with computer expertise and with providing the group with money.